Edible composition containing a polysacchride-producing enzyme

ABSTRACT

A functional food which comprises a glucosyltransferase and/or a fructosyltransferase each having a water-soluble polysaccharide production ability, and a base therefor.

TECHNICAL FIELD

The present invention relates to a novel functional food or ediblecomposition having a calorie intake lowering function.

BACKGROUND ART

Polysaccharide-producing enzyme (glycosyltransferases) such asglucosyltransferase(GT) and fructosyltransferase(FT) are previouslyutilized for, for example, the industrial production of dextran, butsince this polysaccharide-producing enzyme has, in relation to livingbodies, a plaque formation ability in the oral cavity, they have beenregarded as the most important pathogenic factor of dental caries, andtherefore, their utilization has been limited.

DISCLOSURE OF THE INVENTION

The object of the present invention is to provide a functional food oredible composition having a calorie intake lowering function.

According to the present invention, there is provided a functional foodcomposition comprising at least one polysaccharide-producing enzymeselected from the group consisting of glucosyltransferases andfructosyltransferase having a water soluble polysaccharide productionability, and a base therefor.

BEST MODE OF CARRYING OUT THE INVENTION

As a result of intensive studies, the present inventors found that, whena water-soluble enzyme having a polysaccharide production capability isselected from the polysaccharide-producing enzymes, it does not become adental caries pathogenic factor and forms polysaccharide from sucrose inthe digestive tract to lower the calorie intake, and thus there can beprovided a food or edible composition useful for the prophylaxis ofadult disease factors such as obesity.

The constitution and effects, etc., of the invention are described indetail below.

ORIGIN OF THE ENZYMES

The enzymes GT and FT can be produced by the following bacteria.Examples of such bacteria are lactic acid bacteria (Streptcoccussalivarius, S. bovis and S. sunguis), Bacillus natto (Bacillussubtilis), molds (Aspergillus niger, Aspergillus oryzae, Aureobasidumpullulans), and plants (onion: Arium sepa). The following strains areexemplified as particularly useful: B. subtilis IAM 1168, S. salivariusATCC 9758, S. bovis ATCC 9809, A. pullulans IAM 5060, Asp. niger ATCC10864 and Asp. oryzae ATCC 1011.

CONSTITUTION OF THE EDIBLE COMPOSITION

When the above enzyme is orally ingested, the activity thereof isreduced by a digestive fluid such as the gastric juices, and to preventthis, the present composition can be constituted in usual enteric dosageforms such as gelatin capsules, or granules, or tablets coated withhydroxypropyl methyl cellulose or the like; gel-like dosage forms suchas sodium alginate capable of reducing the gastric juice effect; and fatand oil-like dosage forms.

The amount of the polysaccharide or oligosaccharide-producing enzymeformulated in the edible composition according to the present inventionvaries depending upon, for example, the use and dosage form thereof, andis not particularly limited.

Bases used in edible compositions according to the present inventionvary depending upon the forms of the compositions, and in addition tothe case whereby the enzyme is added as it is, for example, in the caseof a gel-like dosage form, there can be used a base obtained bydissolving the enzyme in a mixed solution of sodium alginate (0.2 to2%), agar (0 to 5%) and gelatin (0 to 15%) and allow the solution to begelled by cooling or drying, or a base obtained by drying the gelledproduct. On the other hand, in the case of a fat and oil-like dosageform, a fat and oil having a freezing point of 37° C. or more, forexample, a hydrogenated oil of a vegetable fat and oil such as rapeseedoil (a fat or oil having a freezing point of 37° to 70° C. is obtainedaccording to the degree of hydrogenation) is used. The fat and oil isheated and melted, the enzyme is then added at 1/20 to the equal weight,based upon the fat and oil, and the mixture is mixed and coagulated toobtain a fat and oil dosage form. As another dosage form, there can bementioned the enzyme coated with an enteric material such ashydroxypropyl methyl cellulose or zein, i.e., a granule or tablet of theenzyme coated therewith, in which the enteric material is used in 1/20to equal weight based upon the enzyme in the case of a coated granuleand in an amount of 0.5 to 3% of a tablet in the case of a tablet.Further, in foods containing much animal protein including milk, thehigh pH buffering ability thereof can inhibit the gastric acidity, andthus there can be mentioned the addition of the enzyme into such foodsor meat products after cooking.

Components appropriately formulated into ordinary foods such as, forexample, starches, powder milk or other milks or milk products, casein,soybean protein, seasonings such as amino acids, chocolate rawmaterials, flour, perfumes and coloring matters can be compounded asoptional components into the edible composition of the presentinvention.

OTHER PHYSIOLOGICAL EFFECTS

Foods or edible compositions according to the present invention have, inaddition to the calorie intake lowering function, a selectiveproliferation effect on the intestinal useful bacteria due to theproduced polysaccharides or oligosaccharides. Namely, for example, thepolysaccharides and the like by the S. salivarius-derived enzyme canselectively proliferate S. salivarius, S. bovis and L. acidophilus, andoligosaccharides mainly bacteria of the genus Bifidobacterium.

EXAMPLES

The present invention is described in more detail below with referenceto the following Examples, which by no means limit the scope of thepresent invention.

Example 1: Preparation of a polysaccharide-producing enzyme

S. salivarius ATCC 9758 is given as an example.

The ATCC 9758 strain was inoculated with an initial viable cell count of10⁶ /ml into a SYPT medium (10% sucrose, 1% yeast extract, 1% peptone,0.1% Tween 80) and cultured at a temperature of 37° C. and a pH of 7.0under an aerobic condition.

A dropwise addition of a 5N NaOH solution prevented the pH loweringaccompanying lactic acid fermentation, and the pH of the system wasmaintained at a constant value. After 7 hours culturing, the culturebroth was subjected, for example, to filtration with a membrane filter(0.1μ filter produced by ASAHI CHEMICAL INDUSTRY CO , LTD.) orcentrifugation (10,000×g), and the resulting culture supernatant wasconcentrated and desalted by using an ultrafiltration membrane having afractionation molecular weight of about 15,000 (produced by MitsuiPetrochemical Industries, Ltd). The concentration and desalting also canbe carried out by adding ammonium sulfate to a 50% saturation thereofunder ice cooling, centrifuging the mixture at 15,000×g, and dialyzingthe precipitate using distilled water as an outer fluid. The yield ofthe enzyme preparation by the present method was about 2500 U or moreper liter of the culture broth.

Example 2: Measurement of the activity of the polysaccharide-producingenzyme

A 10 mg amount of the enzyme preparation was dissolved in 1 ml ofdeionized water, 0.1 ml thereof was dissolved in 3.2 ml of a phosphatebuffer (pH 6.0, 0.05M) containing 2% sucrose, an enzymatic reaction wascarried out at 37° C. for 10 minutes, and 0.7 ml of a 2N NaOH solutionwas added to terminate the reaction.

The reaction solution was neutralized and dialyzed (the outer fluid wasdistilled water) at 60° C. for 20 hours, and the polysaccharide amountproduced in the resulting reaction solution was determined by measuringthe volume of the dialysis inner fluid and the polysaccharideconcentration thereof by the phenol-sulfuric acid method, andmultiplying the obtained values. The polysaccharide formation amount wasdetermined by subtracting the polysaccharide amount before the 10minutes reaction from the polysaccharide amount after the 10 minutesreaction. The 1U was defined as the enzyme preparation amount used forthe formation of 1 mg of polysaccharide from sucrose, for 1 minute.

The weight of the serum triglyceride and fat tissues was measured whenfructosyltransferase was ingested, together with sucrose, by rats. Theresults are shown below.

Influence of the fructosyltransferase (F Tase) agent on rat serumtriglyceride and fat tissue weight

    ______________________________________                                        Serum TG (mg/dl)         Fat tissue                                           3W               4W          weight                                           ______________________________________                                        Normal  .sup.  216 ± 19.5.sup.a)                                                                    200 ± 17.1                                                                             2.33 ± 0.14                           diet group                                                                    40% su- 286 ± 20.6    346 ± 50.1                                                                             2.95 ± 0.09                           crose diet                                                                    group               *             *           *                               40% su- 235 ± 11.4    260 ± 25.4                                                                             2.50 ± 0.21                           crose diet                                                                    group                                                                         +FTase group                                                                  ______________________________________                                    

Rats (Wister, , 6 weeks old, 5 animals per group) were bred for 4 weeksunder set diet conditions. A FTase enzyme preparation of about 680 U/gwas added to 0.5% (1U is an enzyme amout required to form 1 g of thepolysaccharides per one hour).

a) mean±S.E.

*) p<0.05

Example 3: Preparation of gel-like and fat and oil-like dosage forms

1. Gel-like dosage form

As hereinafter described, a jelly obtained by adding sodium alginate toagar gel effectively retains an enzymatic activity even under an acidiccondition, and is useful for the protection of the enzyme from thegastric juice, similar to general enteric preparations. The basecomposition of the jelly with addition of alginic acid is given below.

    ______________________________________                                        Sodium alginate  1%     (generally 0.5 to 2%)                                 Gelatin          2%     (generally 0 to 10%)                                  Agar             1.3%   (generally 0 to 2%)                                   Potassium phosphate                                                                            1.5%   (pH of 6.5 is                                                                 obtained)                                             ______________________________________                                         (pH usually maintained at 5 to 7.5)                                      

The activity expression of the polysaccharide-producing enzyme was notinfluenced by adding, as a sweetener, mannitol or xylose or anotherflavoring. The base was sufficiently melted at about 100° C. and waskept warm at about 45° to 50° C. The above enzyme preparation was addedto this sol at a rate of 50 mg (12.5 U) per ml of the sol, and themixture was mixed and allowed to cool to obtain a coagulated substance.This gel can further be air-dried overnight at room temperature toprepare a dried substance having an enzymatic activity.

2. Fat and oil-like dosage form

Hydrogenated oils having a melting point in the range of 38° to 70° C.have a coating effect and protect the polysaccharide-producing enzymefrom the gastric juices. Particularly, hydrogenated oils having amelting point of 38° to 42° C., higher than the body temperature by 1°to 4° C., have the same effect in a jelly-like dosage form. A method ofpreparing a hydrogenated palm oil having a melting point of 38° C. isdescribed herinafter as an example.

1 g of a hydrogenated palm oil (produced by NIPPON OIL AND FATS CO.,LTD.) was melted by heating at a temparature of 45° C., 0.56 g (140 U)of the polysaccharide-producing enzyme was added, 90 mg of potassiumphosphate was added, and the mixture was mixed and allowed to coolovernight at room or a low temperature, to be coagulated, whereby thedesired fat and oil-like dosage form was obtained.

Example 4: Protection from gastric juices by gel-like and fat andoil-like dosage forms

1. Gel-like dosage form

The activity of the polysaccharide-producing enzyme to be added to thebase was measured before preparing a gel-like agent.

A physiological saline of pH 3.0 containing 0.1% pepsin (produced byWako Pure Chemical Industries, Ltd.) was prepared as an antificialgastric juice, and to 1 l thereof were added 10 g (0.7 g as the driedjelly, 125 U), of the gel-like agent prepared in Example 3, and 40 g ofsucrose. After one hour's shaking at 37° C., the pH was increased to 7.2to 7.5 with a 2N NaOH aqueous solution, 0.1% pancreatin was added, andfurther, a total of two hours incubation was carried out. Thepolysaccharide formation amount was measured by sampling at intervals.This measurement was made by adding 0.5 ml of a 5N NaOH aqueous solutionto 9.5 ml of the sampled fluid, to neutralize the same, and using thesame method as the above activity measurement method. The formation ofpolysaccharides was not observed in the gel-like agent to which alginicacid was not added (Comparative Example). The results are shown in Table1.

2. Fat and oil-like dosage form

A 1 g (90 U) amount of a fat and oil-like agent comprising thehydrogenated oil prepared in Example 3 and the polysaccharide-producingenzyme was added to an antificial gastic juice in the same manner as forthe gel-like dosage form, and sampling at intervals and the measurementof the polysaccharide formation amount were carried out. The results areshown in Table 1.

                  TABLE 1                                                         ______________________________________                                        Polysaccharide formation amount in the artificial gastric                     juice (ml/l/U)                                                                         Jelly-like agent  Fat and                                            Sampling time                                                                            No addition of                                                                             Addition of                                                                              oil-like                                   (mt)       alginic acid alginic acid                                                                             agent                                      ______________________________________                                         0         0.32         0.48       0.78                                       20         0.40         2.08       1.11                                       60         0.72         3.28       5.00                                       80         1.44         12.2       9.78                                       120        1.44         20.0       17.7                                       ______________________________________                                    

We claim:
 1. An edible composition in gel dosage form comprising at least one polysaccharide or oligosaccharide-producing enzyme selected from the group consisting of glucosyltransferase and fructosyltransferase wherein said enzyme has the ability to produce a water-soluble polysaccharide from sucrose, and said enzyme being mixed in a base solution therefor containing 0.5 to 2% sodium alginate, 0 to 10% gelatin and 0 to 2% sodium.
 2. An edible composition in granular form comprising at least one polysaccharide or oligosacharide-producing enzyme selected from the group consisting of glucosyltransferase and fructosyltransferase wherein said enzyme has the ability to produce a water-soluble polysaccharide from sucrose, and said enzyme being coated with an enteric material selected from the group consisting of hydroxypropyl methyl cellulose, carboxymethyl ethyl cellulose, zein, and shellac, wherein the enteric material is used in 1/20 to equal weight based upon the enzyme.
 3. An edible composition in tablet form comprising at least one polysaccharide or oligosaccharide-producing enzyme selected from the group consisting of glucosyltransferase and fructosyltransferase wherein said enzyme has the ability to produce a water-soluble polysaccharide from sucrose, and said enzyme being coated with an enteric material selected from the group consisting of hydroxypropyl methyl cellulose, carboxymethyl ethyl cellulose, zein, and shellac, wherein the enteric material is used in an amount of from 0.5 to 3% based upon the enzyme. 